Hybrid lock



May 19, 1970 M. M. CHECK TAL f 5 238 HYBRID LOCK Filed April 17, 1968 4 Sheets-$het 1 mi k INVENTORS Mam/4s M Cam w M411 ffl mr/ 6777 5y 5 V W/c s May 19, 1970 M. M. CHECK ETAL 3,512,382

HYBRID LOCK 4 Sheets-Sheeb 2 Filed April 17, 1968 INVENTORS AM/As /7 695% BY 60? Wuw SQUWAQVA 4/77/7677? 7/ E /m May 19, 1970 M. M. CHECK T HYBRID LOCK Filed April 17, 1968 4 Sheets-Sheet 5 m5 MW w WC 6 r 42 A m We mm 7 mm? May 19, 1970 M. M. CHECK ETAL 3,512,382

HYBRID LOCK Filed April 17, 1968 4 Sheets-Sheet 4.

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- INVENTORS MAW/AS M CHECK y Guy Mfl go United States Patent US. Cl. 70-276 2 Claims ABSTRACT OF THE DISCLOSURE The lock arrangement disclosed in the following specification combines in a single cylinder and body, (1) the mechanical locking technique employing spring loaded pin tumblers, which are actuated by a splined key and (2) magnetic tumblers which are actuated by a magnetic key. By means of a single key and a single cylinderbody combination with a single keyway, advantage is taken of both the mechanical and magnetic locking features. In this fashion a lock having greatly enhanced security is provided and, in particular, the lock having this combination of mechanical and magnetic tumbler features is made nearly pick proof.

BACKGROUND OF THE INVENTION This invention relates to an improved lock and more particularly to a lock having both pin tumblers and mag netic tumblers.

There are many known or proposed types of magnetic tumbler locks in several different configurations. In the best of these the reliance on magnetic operation renders them relatively secure from being picked. However, although the techniques of picking a magnetically actuated pin tumbler lock are not nearly as simple and standard as are the techniques of picking the usual spring loaded pin tumbler lock, nonetheless it is quite feasible to pick (or compromise as it is sometimes called) such magnetic locks. Oneway of compromising a magnetically actuated pin tumbler lock is to employ a master key having openings adapted to receive and hold key magnets so that various combinations of key magnet polarities can be run through. Each combination is then tested in the lock until the combination that opens the lock is achieved. If the lock has four magnetically actuated pin tumblers, then at most sixteen and on the average eight combinations would be required in order to open the lock. For more sophisticated magnetic locks, such an approach might have to be supplemented by the use of a small magnetic probe to determine the location and perhaps even the polarity of the various magnetically actuated pin tumblers. In any case, techniques are known for compromising magnetic locks.

Increasing the number of tumblers in a pin tumbler lock or a magnetic tumbler lock gives some increased security. However, such changes merely increase the time and elfort expended before the lock can be picked. However, increasing the number of tumblers adds significantly to the size, cost, and complexity of the lock. Thus the increase in security is purchased at a cost of size and complexity that, from a practical point of view, limits the security attainable.

There have been many improvements in both magnetic tumbler locks and ordinary pin tumbler locks which have added to their providing security. However, these improvments have not altered the basic method of comprising these locks.

Accordingly, it is a major purpose of this invention to provide substantially increased lock security over that available with comparable locks having solely spline "actuated or solely magnetically actuated tumblers.

The environment within which many types of locks, particularly the mortise type of lock, must operate is one that limits the length of the lock. The width of a door or other such similar closing mechanism limits the length of the lock and thus puts :an upper limit on the number of tumblers which can be added in order to add complexity and increase lock security.

Accordingly, it is a specific purpose of this invention to provide increased security for a tumbler lock having a given length.

More specifically, it is a purpose of this invention to provide substantially increased lock security for a given number of tumblers.

It is a further important purpose of this invention to achieve all the above purposes in a lock design that is sufliciently simple and inexpensive so as to be usable in "a wide variety of situations.

SUMMARY OF THE INVENTION In brief, the lock has a number of tumblers radially disposed relative to the main axis of the lock. These tumblers are of two types: spring loaded pin tumblers and magnetic pin tumblers. The lock of the invention is adapted to receive a splined key having at least one spline disposed longitudinally along the outer surface of the key. The key also has recesses therein for receiving key magnets for attracting and/ or repelling the magnetic pin tumblers into an unlocking position.

Upon placing the key into the keyway provided therefor in the lock, the spline displaces a corresponding set of pin tumblers such that when the key is in the fully inserted position all the pin tumblers are free of the parting line. Each key magnet simultaneously attracts or repels one of the magnetic pin tumblers so that they clear the parting line and the lock is then free to rotate. The lock disclosed herein has solved a problem at the heart of the lock industry, namely the lock that is virtually pick proof and is yet not so complex as to be commercially impractical.

The lock of the invention when compared with a lock, either magnetic or spring loaded, of the same number of tumblers, provides markedly increased security since two distinct locking techniques are made compatible in a way that requires two incompatible techniques to be employed in compromising the lock.

An additional element of security is provided by placing the tumblers of both types at diiferent radial positions.

The magnetic tumblers in this invention can be all in attraction, all in repulsion, or part in attraction, part in repulsion.

The combination of magnetic pin tumblers and spring loaded pin tumblers utilized in the lock of the invention also provides a dramatic increase in the number of usable opening commbinations. One embodiment hereinafter described has around twenty million useful combinations.

BRIEF DESCRIPTION OF DRAWINGS Other objects and purposes of this invention will be obvious from the following detailed description and drawings, in which:

FIG. 1 is an exploded perspective view of a first embodiment of this invention showing a three splined key and a lock having nine spring load pin tumblers and three magnetic tumblers;

FIG. 2 is a longitudinal sectional view of the FIG. 1 look with a key in place and all tumblers free of the parting line;

FIG. 3 is a cross-sectional view along line 3--3 of the lock shown in FIG. 2;

FIG. 4 is an exploded perspective view of a key for the FIG. I lock;

FIG. 5 is a transverse sectional view of an alternative embodiment of this invention;

FIG. 6 is a cross sectional view, along the plane 6-6 of the FIG. 5 lock, with the proper key inserted so that the tumbler magnets are in the unlocking state;

:FIG. 7 is a broken away longitudinal view of the body portion of a variation in the FIG. 5 embodiment;

FIG. 8 is a cross sectional view, similar to that of FIG. 6 except that the FIG. 8 cross section is a lock designed in accordance with the FIG. 7 variation, and with the key removed so that the tumbler magnets are shown in the locking position; and

FIGS. 9a and 9b are cross sectional views (similar to that of FIG. 6) of the FIG. 5 type of embodiment wherein the operative magnetic action between the key magnets and the tumbler magnets is magnetic repulsion rather than magnetic attraction.

DESCRIPTION OF THE PREFERRED EMBODIMENTS The FIG. 1 embodiment: In the embodiment of the lock shown in FIG. 1, there are three coaxial cylindrical members each of which must be made of a non-magnetizable material. The inner member is the cylinder 18, the intermediate member is the lock body and the outer member is a shell 22. The cylinder portion 18 has a slip fit relationship with the body portion 20 so that the cylinder 18 will turn within the body 20 during locking and unlocking. A generally cylindrical keyway 24 having grooves to receive splines is within the cylinder 18 and is designed to receive the key 25.

Nine passageways 26 (six of which are shown) extend radially from within the cylinder 18 through the body 20 te accommodate nine spring loaded pin tumblers 28. These nine passageways 26 for the spring loaded tumblers 28 are grouped in sets of three, each set of three lying in a separate radial plane passing through the longitudinal axis of the body 20. Each of these three planes are at an angle of 120 from its adjacent plane. In addition, each of the pin tumbler passageways 26 is in a separate cross sectional plane so that the nine pin tumblers 28 are lonigtudinally displaced from one another and thus 'when the cylinder 18 is rotated within the body 20, no one of the pin tumblers 28 can jam the look by falling into a passageway 26 that is associated with some other tumbler.

Each spring loaded pin tumbler 28 has an inner portion 280, an outer portion 28b and a spring portion 28s. When the key is inserted into the lock, the tumblers 28 are radially displaced so that the plane of separation of between the inner portion 28a and upper portion 28b is a continuation of the parting line 32 of the lock (see FIGS. 2 and 3). The parting line 32 is the surface of contact between the body 20 and the cylinder 24. The radially outward end of the spring portion 28s rests against the inner surface of the shell 22 when the lock is assembled so that the springs 28s are always in compression.

In addition to the nine spring loaded pin tumbler 28 arrangement described, the FIG. 1 embodiment has three magnetic tumblers 34. Three passageways 26 extend radially outward from within the cylinder 18 to within the body 20 to accommodate these magnetic tumblers 34. The passageways 36, in the FIG. 1 embodiment, are not only displaced from one another along the longitudinal axis of the lock but are also 120 radially displaced from each other. In addition, the radial position of the passageways 36 for the magnetic tumblers 24 is radially displaced from any of the passageways 26 of the spring loaded pin tumblers 28.

At the radially outward end of each passageway 36 within which the magnetic tumblers 34 are located, there is a spacer 38 made of non-magnetizable material which serves to spearate the magnetic tumblers 34 from an insert 40 made of magnetizable material.

The key 25, employed to actuate these spring loaded tumblers 28 and magnetic pin tumblers 24, has a generally cylindrical shank 41 on which are mounted three splines 42. The splines 42 are spaced from each other around the circumference of the shank 41. Only two of these splines 42 are shown in FIG. 1. Each of the splines 42 has the indentations 44 necesasry to raise corresponding pin tumblers 28 to the height necessary to open the lock. In addition, the key 25 contains three bar magnets 46 buried in the shank 41 at appropriate axiai positions and angular orientations to actuate the three pin tumbler magnets 34 and move these tumbler magnets 34 to a position on one side of the parting line 32 so as to permit opening the lock.

As may be seen from FIGS. 2 and 3, when the key 25 is inserted into the keyway 24 the various indentations 44 are mated with the appropriate spring loaded pin tumblers 28 to align the inner portions 28a and outer portions 28b of each pin tumbler 28 with the parting line 32. In addition, each key magnet 46 attracts one of the magnetic pin tumblers 34 radially inward so that the magnetic pin tumbler 34 clears the parting line 32 and permits the cylinder 18 to be turned within the body 20. In the embodiment shown, the magnetic operation is in magnetic attraction. Specifically, this means that each key magnet 46 has a polarity such as it will attract the corresponding pin tumbler magnet 34.

When the key 25 is removed the pin tumbler magnet 34 is attracted by the magnetizable insert 40 to a radially outward position so that the pin tumbler magnet 34 serves to lock the cylinder 18 to the body 20. To perform this function it is not necessary that the magnetizable material insert 40 be magnetized since a magnet 34 will attract itself to any adjacent magnetizable material such as iron. Of course, the insert 40 could be made to be a magnet in which case, in the example shown in FIG. 2, the insert 40 would have to have its north pole radially inward so as to tend to attract the magnet 34. In any case, the dimensional arrangement and relative strength of the magnetic fields must be made such that when the key 25 is inserted the key magnet 46 will overcome whatever force of attraction there is between the tumbler magnet 34 and the insert 40 to move the tumbler magnet 34 radially inward. The non-magnetizable insert 38 is essential to assure the proper balancing of magnetic forces since otherwise the proximity of the insert 40 and pin tumbler magnet 34 when in the unlocking position would be so great as to make it unfeasible if not impossible for any magnet in the key 25 to overcome the strong force of attraction that would occur were the insert 40 and pin tumbler 34 to be in contact at any time.

Obviously, if this magnetic effect is to be employed neither the cyiinder 18 nor the body 20 can be made of a magnetizable material.

The embodiment shown in FIG. 1 employs magnetic attraction for moving the magnetic tumbler 34 in its passageway 36. However, one or more of the magnetic pin tumblers could be operated upon by means of magnetic repulsion as is described in the Felson Pat. No. 3,111,834.

The FIG. 1 embodiment is designed to provide not only as much security as possible but also a very wide variety of combinations. Accordingly, a three spline arrangement is shown so as to make possible the use of nine spring loaded tumblers. Obviously, if a reduced number of key combinations were acceptable the number of splines could be reduced.

In the three spline embodiment iiiustrated, wherein the splines are spaced 120 from one another, there must be some aligning feature so that the user is in a position to determine the key 25 orientation when inserting the key into the key hole. For that purpose, a slot 49 in the key way 24 and matching pin 50 in the key 25 is employed.

With the key 25 inserted as described above, the cylinder 18 can be rotated. The rotation of the cylinder 18 results in the shifting of a bolt. In order for the FIG. I lock to be employed with presently designed locking arrangements, wherein the bolt is ofiset from the center line of the lock itself, the FIG. 1 design includes a gear train composed of gears 52 and 54 to carry the rotating action of the plug through to the ofiset bolt. As will be seen in connection with the FIG. embodiment, it is possible to simplify this coupling between the cylinder 18 and the bolt by offsetting the cylinder 18 within the body 20. However, the FIG. 1 embodiment, which is intended to provide a maximum number of combinations together with maximum security, requires that the various spring loaded pin tumblers 28 and magnetic pin tumblers 34 be radially displaced from one another and thus requlres, for reasons of space, that the cylinder 18 be centrally disposed within the body 20.

FIG. 4 illustrates an exploded view of the make up of the key 25. As may be seen, the shank 41 is essentially a two piece item having an outer tubular sheath portion 41a that fits over an inner cylindrical unit 41b. Within the inner cylindrical unit 41b there are three openings 56 into which the bar magnets 46 fit. The bar magnets 46 are held in place when the tubular sheath 41a is fit over the inner cylindrical piece 41b. The guide pin 50 holds the sheath 41a to the inner tubular portion 41b.

FIG. 5 embodiment: FIGS. 5 through 7 illustrate a second and somewhat simplified embodiment of the invention. This second embodiment is adapted to permit the use of numerous standard lock parts and is particularly adapted to a simple design which can be incorporated in presently designed equipment requiring locks.

This second embodiment, like the first embodiment, takes advantage of the fact that the combination of mechanically actuated spring loaded pin tumblers and magnetically actuated magnetic tumblers in a single lock cylinder and body generates uniquely difiicult problems for anyone attempting to pick or compromise the lock. To the extent possible parallel reference numbers are used to designate comparable parts in the second and first embodiments. Thus the cylinder 18 in the FIG. 1 embodiment and the cylinder 118 in the FIG. 2 embodiment are designated with the same last two digits.

As may be seen in FIGS. 5 and 6, the cylinder 118 is eccentrically mounted Within the body 120 as in standard lock making practice. Accordingly, the key 125 has only one spline 142 and there is but one line of spring loaded pin tumblers 128, the line of movement of each of the pin tumblers 128 being in a common plane. Four of the five spring loaded tumblers 128 are of the known mushroom type which tend to make a lock harder to pick because when torque is applied to the cylinder 118, the lip 129 of one or more of the mushroom tumblers 128 may become caught on the shoulder that tends to be formed along the parting line 132. One of the spring loaded pin tumblers 128 is of the straight cylindrical type in order to assure proper alignment between the cylinder 118 and body 120'.

Because the keyway 124 (and cylinder 118) is offset within the body 120, a standard actuating mechanism 158 can be employed to move the bolt and thus the details of the actuating mechanism 158 are not shown.

There are four magnetic pin tumblers 134 (one of which is shown in FIG. 6) deployed along a horizontal plane within the cylinder 118 of the lock. Each magnetic tumbler 134 is positioned within a passageway 136 so that the line of movement of the magnetic tumbler is along its longitudinal axis. The passageways 136 are so oriented that each magnetic tumbler moves along a line perpendicular to the plane of the spline 142 and thus perpendicular to the line of movement of the spring loaded tumblers 128. Because of this arrangement of the line of movement of the magnetic pin tumbers 134, the shank of the key need not be circular in cross section as was the key 25 in the FIG. 1 embodiment.

In the FIG. 5 embodiment illustrated, the magnetic pin tumblers 134 are all designed to operate in magnetic attraction. Thus, when the key 125 is inserted into keyway 124, each one of the key magnets 146 will attract a separate one of the pin tumbler magnets 134 to a radially inward end position so that the magnetic tumblers 134 clear the parting line 132 between cylinder 118 and body 120. The passageway 136 within which each of the magnetic tumblers 134 is movable extends from within the cylinder 118 to within the body 120. When the key 125 is removed, each pin tumbler magnet 134 moves radially outward within its passageway 136 under the influence of the influence of the magnetic attraction between the pin tumbler 134 and a plug of magnetizable material A spacer 138 of non-magnetizable material must, of course, be inserted between the magnetizable material plug 140 and each pin tumbler 134 magnet, for the same reason as in the FIG. 1 embodiment; which is essentially to make sure that the force of attraction in the locked position can be overcome by the key magnets 146 and thereby permit this lock to be unlocked.

In a preferred design for this second embodiment, the pin tumbler magnets 134 are arranged in alternate fashion on opposite sides of the keyway 124. This has the important advantage of minimizing the magnetic interreaction between tumbler magnets 134. One benefit of minimizing tumbler 134 inter-reaction is a reduction of the sliding friction of these pin tumbler magnets 134 within their passageways. This reduction of sliding friction provides greater assurance of proper operation under attraction of the key magnets 146.

As can be seen from FIG. 5, each of the magnetic pin tumblers 34 are in separate cross sectional plane from each of the spring loaded pin tumblers 128. This is to assure that upon rotation and unlocking of the cylinder 118 in the body 120, none of the spring loaded tumblers 128 will catch on the openings into the passageways 136 for the magnetic tumblers 134.

Because of the use, in the FIG. 5 embodiment, of standard body 120 and cylinder 11'8 relationships, there is not enough room to include magnetic tumblers 134 (which are approximately one-eighth of an inch long) at all radial positions and thus the arrangement whereby the magnetic tumblers 134 are arranged in a plane perpendicular to the spring loaded tumblers 128 has been found preferable. Such arrangement also facilitates the use of a flat key 125, having a thickness only enough to accommodate the one-eighth inch long key magnets 146.

FIGS. 7 and 8 represent a variation of the FIG. 5 embodiment.

A standard technique of manufacturing the lock body 120 is by compressed powdered metallurgy. As is well known, such a fabrication technique permits the ready fabrication of openings and passages in only one direction. The body 120 has to be made with an axial opening to receive the cylinder 118. Thus, the passageways 136' for the magnetic tumblers 134 and for holding the non-magnetizable inserts 138 and magnetizable plugs 140' would normally have to be drilled after the body has been fabricated. The body design shown in FIGS. 7 and 8 provides certain fabrication advantages. As may best be seen in FIG. 7, two axial openings are molded (one on each side of the keyway) into the body 120. The bars of magnetizable material 140' are inserted through these axial openings to form the magnetizable material mass that must be present to attract the tumbler magnets 134 to the radially outward position (shown in FIG. 8) once the key 125 is removed.

In addition, the small portion of the passageways 136 which must be open and extend into the body 120 can be replaced by two grooves 162 running axially along the parting line 132 (one on each side of the keyway). In

one embodiment, the grooves are 0.30 inch deep and provide sufficient depth to cause the 0.135 inch long pin tumbler magnets 134 to lock the cylinder 118 to the body 120 when the pin tumbler magnets 134 are in the radially outward position. Thus by means of axial openings 160 and axial grooves 162 it becomes unnecessary to drill radial holes through the body 120 in order to accommodate the magnetic pin tumblers 134 or magnetizable material 140. However, it will still be necessary to drill the requires radial openings in the body 120 to accommodate the spring loaded pin tumblers 128. The spacer 138 of non-magnetizable material, required in the FIG. design, becomes, in the FIG. 7 design, the portion of the body 120 that is between the axial grooves 162 and the axial openings 160.

The same or similar reference numerals are used in connection with the FIG. 9 embodiment as used in connection with the embodiment shown in FIGS. 5 and 6 since the only difference in these two embodiments is that in the FIG. 5 embodiment magnetic attraction is used and in the FIG. 9 embodiment magnetic repulsion is employed.

FIG. 9a illustrates the tumbler magnet 134a, 134b condition when the key is removed from the keyway 124 while FIG. 9b illustratees the tumbler magnet 134a, 134k condition when the appropriate key is inserted into the keyway 124.

FIG. 9a is shown with the key removed from the keyway 124 so that the tumbler magnets 134a and 13417 are in the locked state. In this FIG. 9' embodiment wherein magnetic repulsion is employed to lock and unlock, two tumbler magnets 134a and 13411 are employed instead of the single tumbler magnet 134 of the FIG. 5 embodiment. The basic reason for the dual tumbler magnet design is that it is desirable to keep the movement of the tumbler magnets to a minimum; for example, 0.040 inch in one embodiment. Shall small movement of the tumbler magnets is preferable so that the tumbler magnets are never far removed from the magnetic field which causes them to change state. This importance of relatively small magnetic tumbler movement applies as much to the FIG. 5 embodiment (employing magnetic attraction) as it does to the FIG. 9 embodiment (employing magnetic repulsion).

It is desirable to have the tumbler magnets 134 located as close to the keyway 124 as possible so that the key magnets 146 need not have excessively large magnetic fields of force. It thus becomes necessary that the radially inward segment 134a of the locking magnet in the FIG. 9 embodiment be relatively lengthly. When the key is inserted in the keyway 124, the tumbler magnets 134, 134b is repelled a short distance (much less than the length of the inbound segment 134a of the tumbler magnets) to a radially outward position. At this radially outward position, the junction between the two locking magnets 134a and 134k is aligned with the parting line 132 between the body 120 and cylinder 118. Thus the lock can be opened without requiring movement of the tumbler magnets 134 to a position completely outside of the cylinder 118.

In addition to the dual tumbler magnet 134a, 134b, it is important to realize that an auxiliary magnet 140a must be employed, rather than the plug of magnetizable material 140. When employing magnetic repulsion, the auxiliary magnet 140 as is required to place the FIG. 9 lock into the locked state. As shown in FIG. 9, the auxiliary magnet 140a operates to repel the tumbler magnets 134a, 134b to the radially inward position. In that position, the tumbler magnet 134b is astride the parting line 132 and thus puts the lock into the locked state.

Accordingly, it is actually the magnet 134b whose position serves to determine the state of the lock. It should be understood that the reference to a tumbler magnet in the broader claims refers to this tumbler magnet 134k.

It should be noted in connection with the FIG. 5 embodiment, as is true with the FIG. 1 embodiment, that the line of action of each tumbler whether it be the spring loaded pin tumblers 2'8, 128 or the magnetic tumblers '46, 146, is such as to intercept a single common keyway 24, 124. Thus not only is a single cylinder 18, 118 and lock body 20, 120 involved, with all of the advantages that provides, but more importantly from the view of security, the single keyway 24, 124 makes it uniquely difiicult for one wishing to compromise the lock to simultaneously insert the mechanical and magnetic tooling or equipment necessary into the keyway to effect the picking of the lock.

A further and very important reason why this hybrid lock design provides maximum security is that even if it were possible to simultaneously undertake the actions necessary to pick the spring loaded pin tumblers 28, 128 and to compromise the magnetically actuated pin tumblers 34, 134, there is the significant fact that the picking and compromising techniques required are mutually selfdefeating. The crucial reason for this is that the spring loaded pin tumblers 28, 128 must be picked while applying a torque to the cylinder whereas the magnetically actuated pin tumblers 34, 134 have to be compromised before torque is applied to the cylinder. The magnetically actuated pin tumblers are actuated by relatively small radial forces compared to the radial forces employed in picking the spring loaded pin tumblers. Therefore, if torque is applied to the cylinder relative to the body of the lock, there is a very strong likelihood that one or more of the magnetically actuated tumblers will be caught in the locking position against the wall of its passageway 36, 136, with sufiicient friction so that even if the proper key arrangement were being inserted, the magnetic forces involved would not be enough to cause the magnetic pin tumblers to move against the force of friction. If the torque were relaxed so as to allow the magnetically actuated pin tumblers to move then the spring loaded pin tumblers would snap back into the locking position. This makes the problem of picking the hybrid lock of this invention uniquely diflicult and thus provides an extremely secure lock of relatively simple design and having a cost of manufacture that is reasonable compared to the security offered.

From the above, it may be seen that the objects of this invention are achieved by providing both spring loaded pin tumblers and magnetic pin tumblers, both of which are actuated from a common keyway. Thus a single key having both a notched spline and bar magnet inserts is required. However, to pick such a lock requires the simultaneous detection and actuation of both spring loaded pin tumblers and magnetically actuated spring tumblers. Since two entirely different detection and picking techniques are required in order to compromise such a lock, since they must be performed simultaneously, since they must be performed by means of entry and operation through a common keyway, and since the two techniques of picking require mutually self-defeating actions, this lock provides a virtually impossible to pick design.

What is claimed is:

1. A pick resistant lock having a cylinder, a keyway extending longitudinally within the cylinder, the cylinder being rotatable within a body when in the unlocked state, compnsing:

a plurality of spring loaded pin tumblers actuable by the spline of a key inserted in said keyway, the line of movement of said spring loaded pin tumblers lying in a first common plane, and

a plurality of magnetic pin tumblers actuable by key magnets inserted in said keyway, successive ones of said magnetic tumblers being substantially radially displaced from each other around said keyway of said cylinder,

the line of movement of each of said magnetic pin tumblers being substantially perpendicular to said first common plane,

each of said magnetic tumblers being a bar magnet longitudinally displaced along said keyway from the cross-sectional planes within which each of the longitudinal axes of said spring loaded pin tumblers lie, whereby upon rotation of said cylinder within said body, none of the spring loaded pin tumblers will contact the passageways associated with said magnetic tumblers.

References Cited other one of said radial end positions placing said tumbler magnet on one side of said parting line 10 thereby placing said lock in an unlocked state,

UNITED STATES PATENTS magnetizable material in said body and positioned 1, 7 2/1916 Fuller 70276 radially outward of each of said magnetic tumblers ,495 7/ 23 Borelli 70358 to provide a magnetic force acting on each of aid 3,6 3 7/ 9 6 Anakln 70364 magnetic tumblers to place said magnetic tumblers 15 1,301 6/1938 Ractliife 70276 in said locking state when the key is removed from 2,370,800 3/1945 K et a1. -1 70352 said keyway, 3,111,834 11/1963 Felson 70276 said longitudinal axis of each of said magnetic tumblers ,541 7/ 1968 Wake 70276 intercepting said keyway so that radially disposed 3, 16,336 12/1968 Felson 70276 bar magnets appropriately placed in said keyway will 2 create a magnetic force acting on each of said magnetic tumblers to place said magnetic tumblers in said unlocked state.

2. The lock of claim 1 wherein:

each one of said magnetic pin tumblers has its longi- 25 tudinal axis lying in a cross sectional plane that is MARVIN A. CHAMPION, Primary Examiner R. L. WOLFE, Assistant Examiner US. 01. X.R. 

